I don't know about the extra wheel bearing stress. So far so good after about 25k miles with the belt. As far as the friction goes, I'm sure that's true, but it is absolutely not noticeable to me. In fact, it seems like the take-off response is better. I don't know if that's just the lack of chain slack or lack of chain noise. But it feels better in the seat of the pants.
Mostly, I just hated lubing my chain and scraping the gunk off my rear wheel, swingarm, etc.
